<template>
	<view class="canvasBox" @touchmove.prevent.stop>
		<template v-if="isUse">
			<view class="box">
				<view class="line"></view>
				<view class="angle"></view>
			</view>
			<view class="box2" v-if="isUseTorch">
				<view class="track" @click="openTrack">
					<svg t="1653920715959" class="icon" viewBox="0 0 1024 1024" version="1.1"
						xmlns="http://www.w3.org/2000/svg" p-id="1351" width="32" height="32">
						<path
							d="M651.353043 550.479503H378.752795L240.862609 364.315031c-3.688944-4.897391-5.660621-10.876025-5.660621-17.045466v-60.040745c0-15.773416 12.847702-28.621118 28.621118-28.621118h502.459627c15.773416 0 28.621118 12.847702 28.621118 28.621118v59.977143c0 6.105839-1.971677 12.084472-5.660621 17.045466l-137.890187 186.228074zM378.752795 598.308571v398.024348c0 15.328199 12.402484 27.667081 27.667081 27.667081h217.266087c15.328199 0 27.667081-12.402484 27.66708-27.667081V598.308571H378.752795z m136.300124 176.942112c-14.564969 0-26.331429-11.76646-26.331428-26.331428v-81.283975c0-14.564969 11.76646-26.331429 26.331428-26.331429 14.564969 0 26.331429 11.76646 26.331429 26.331429v81.283975c0 14.564969-11.76646 26.331429-26.331429 26.331428zM512 222.608696c-17.554286 0-31.801242-14.246957-31.801242-31.801243V31.801242c0-17.554286 14.246957-31.801242 31.801242-31.801242s31.801242 14.246957 31.801242 31.801242v159.006211c0 17.554286-14.246957 31.801242-31.801242 31.801243zM280.932174 205.881242c-9.47677 0-18.889938-4.197764-25.122981-12.275279L158.242981 67.991056a31.864845 31.864845 0 0 1 5.597019-44.648944 31.864845 31.864845 0 0 1 44.648944 5.597018l97.502609 125.551305a31.864845 31.864845 0 0 1-5.597019 44.648944c-5.787826 4.579379-12.656894 6.741863-19.46236 6.741863zM723.987081 205.881242c-6.805466 0-13.674534-2.162484-19.462361-6.678261a31.794882 31.794882 0 0 1-5.597018-44.648944l97.566211-125.551304a31.794882 31.794882 0 0 1 44.648944-5.597019 31.794882 31.794882 0 0 1 5.597019 44.648944l-97.566211 125.551305c-6.360248 8.077516-15.709814 12.27528-25.186584 12.275279z"
							fill="#ffffff" p-id="1352"></path>
					</svg>
					{{ trackStatus ? '关闭闪光灯' : '打开闪光灯' }}
				</view>
			</view>

			<view class="mask1 mask" :style="'height:' + maskHeight + 'px;'"></view>
			<view class="mask2 mask"
				:style="'width:' + maskWidth + 'px;top:' + maskHeight + 'px;height:' + canvasHeight + 'px'"></view>
			<view class="mask3 mask" :style="'height:' + maskHeight + 'px;'"></view>
			<view class="mask4 mask"
				:style="'width:' + maskWidth + 'px;top:' + maskHeight + 'px;height:' + canvasHeight + 'px'"></view>
		</template>
		<template v-else>
			<slot name="error">
				<view class="error">
					<view class="on1">相机权限被拒绝，请尝试如下操作：</view>
					<view>· 刷新页面后重试；</view>
					<view>· 在系统中检测当前App或浏览器的相机权限是否被禁用；</view>
					<view>· 如果依然不能体验，建议在微信中打开链接；</view>
				</view>
			</slot>
		</template>
	</view>
</template>

<script setup>
	import jsQR from 'jsqr'
	const emit = defineEmits(['error', 'success'])
	const props = defineProps({
		continue: {
			type: Boolean,
			default: false // false 监听一次   true 持续监听
		},
		exact: {
			type: String,
			default: 'environment' // environment 后摄像头  user 前摄像头
		},
		size: {
			type: String,
			default: 'whole' // whole 全屏  balf 半屏
		},
		definition: {
			type: Boolean,
			default: false // fasle 正常  true 高清
		}
	})
	const windowWidth = ref(0)
	const windowHeight = ref(0)
	const video = ref(null)
	const canvas2d = ref(null)
	const canvas2d2 = ref(null)
	const canvasWidth = ref(200)
	const canvasHeight = ref(200)
	const maskWidth = ref(0)
	const maskHeight = ref(0)
	const track = ref(null)
	const isUseTorch = ref(false)
	const trackStatus = ref(false)
	const isParse = ref(false)
	const isUse = ref(true)

	/* 展开遮罩 */
	const createMsk = () => {
		maskWidth.value = windowWidth.value / 2 - canvasWidth.value / 2
		maskHeight.value = windowHeight.value / 2 - canvasHeight.value / 2
	}
	/* 展开扫码 */
	const openScan = () => {
		const width = transtion(windowHeight.value)
		const height = transtion(windowWidth.value)
		const videoParam = {
			audio: false,
			video: {
				facingMode: { exact: props.exact },
				width,
				height
			}
		}
		navigator.mediaDevices
			.getUserMedia(videoParam)
			.then(stream => {
				video.value = document.createElement('video')
				video.value.width = windowWidth.value
				video.value.height = windowHeight.value

				const canvas = document.createElement('canvas')
				canvas.id = 'canvas'
				canvas.width = transtion(canvasWidth.value)
				canvas.height = transtion(canvasHeight.value)
				canvas.style = 'display:none;'
				//canvas.style = 'position: fixed;top: 0;z-index: 999;left:0'
				canvas2d.value = canvas.getContext('2d')

				// 设置当前宽高 满屏
				const canvasBox = document.querySelector('.canvasBox')
				canvasBox.append(video.value)
				canvasBox.append(canvas)
				canvasBox.style = `width:${windowWidth.value}px;height:${windowHeight.value}px;`

				// 创建第二个canvas
				const canvas2 = document.createElement('canvas')
				canvas2.id = 'canvas2'
				canvas2.width = canvasWidth.value
				canvas2.height = canvasHeight.value
				canvas2.style = 'position: absolute;top: 50%;left: 50%;z-index: 20;transform: translate(-50%, -50%);'
				canvas2d2.value = canvas2.getContext('2d')
				canvasBox.append(canvas2)

				video.value.srcObject = stream
				video.value.setAttribute('playsinline', true)
				video.value.play()
				tick()

				track.value = stream.getVideoTracks()[0]
				setTimeout(() => {
					isUseTorch.value = track.value.getCapabilities().torch || null
				}, 500)
			})
			.catch(err => {
				isUse.value = false
				emit('error', err)
			})
	}
	/* 识别 */
	const tick = () => {
		if (!isParse.value) return
		if (video.value.readyState === video.value.HAVE_ENOUGH_DATA) {
			canvas2d.value.drawImage(
				video.value,
				transtion(maskWidth.value),
				transtion(maskHeight.value),
				transtion(200),
				transtion(200),
				0,
				0,
				transtion(canvasWidth.value),
				transtion(canvasHeight.value)
			)

			const imageData = canvas2d.value.getImageData(
				0,
				0,
				transtion(canvasWidth.value),
				transtion(canvasHeight.value)
			)

			const code = jsQR(imageData.data, imageData.width, imageData.height, {
				inversionAttempts: 'dontInvert'
			})

			canvas2d2.value.clearRect(0, 0, canvasWidth.value, canvasHeight.value)
			if (code) {
				drawLine(code.location.topLeftCorner, code.location.topRightCorner)
				drawLine(code.location.topRightCorner, code.location.bottomRightCorner)
				drawLine(code.location.bottomRightCorner, code.location.bottomLeftCorner)
				drawLine(code.location.bottomLeftCorner, code.location.topLeftCorner)
				if (code.data) {
					getData(code.data)
				}
			}
		}
		requestAnimationFrame(tick)
	}
	const closeCamera = () => {
		isParse.value = false
		if (video.value && video.value.srcObject) {
			video.value.srcObject.getTracks().forEach(trackItem => {
				trackItem.stop()
			})
		}
	}
	const transtion = (number) => {
		return props.definition ? number * 2.8 : number * 1.8
	}
	const nutranstion = (number) => {
		return props.definition ? number / 2.8 : number / 1.8
	}
	const drawLine = (begin, end, color = '#FF3B58') => {
		canvas2d2.value.beginPath()
		canvas2d2.value.moveTo(nutranstion(begin.x), nutranstion(begin.y))
		canvas2d2.value.lineTo(nutranstion(end.x), nutranstion(end.y))
		canvas2d2.value.lineWidth = 4
		canvas2d2.value.strokeStyle = color
		canvas2d2.value.stroke()
	}
	const getData = (data) => {
		emit('success', data)
		if (!props.continue) {
			closeCamera()
		}
	}
	const openTrack = () => {
		trackStatus.value = !trackStatus.value
		track.value.applyConstraints({
			advanced: [{ torch: trackStatus.value }]
		})
	}
	onMounted(() => {
		if (origin.indexOf('https') === -1) throw '请在 https 环境中使用摄像头组件。'
		windowWidth.value = document.documentElement.clientWidth || document.body.clientWidth
		windowHeight.value = document.documentElement.clientHeight || document.body.clientHeight
		windowHeight.value = props.size === 'whole' ? windowHeight.value : windowHeight.value / 2
		isParse.value = true
		nextTick(() => {
			createMsk()
			openScan()
		})
	})
	onUnmounted(() => {
		closeCamera()
	})
</script>
<style scoped>
	page {
		background-color: #333333;
	}
</style>
<style lang="scss" scoped>

	.canvasBox {
		width: 100vw;
		height: 100vh;
		position: relative;

		background-image: linear-gradient(0deg,
				transparent 24%,
				rgba(32, 255, 77, 0.1) 25%,
				rgba(32, 255, 77, 0.1) 26%,
				transparent 27%,
				transparent 74%,
				rgba(32, 255, 77, 0.1) 75%,
				rgba(32, 255, 77, 0.1) 76%,
				transparent 77%,
				transparent),
			linear-gradient(90deg,
				transparent 24%,
				rgba(32, 255, 77, 0.1) 25%,
				rgba(32, 255, 77, 0.1) 26%,
				transparent 27%,
				transparent 74%,
				rgba(32, 255, 77, 0.1) 75%,
				rgba(32, 255, 77, 0.1) 76%,
				transparent 77%,
				transparent);
		background-size: 3rem 3rem;
		background-position: -1rem -1rem;
		z-index: 10;
		background-color: #1110;
	}

	.box {
		width: 200px;
		height: 200px;
		position: absolute;
		left: 50%;
		top: 50%;
		transform: translate(-50%, -50%);
		overflow: hidden;
		border: 0.1rem solid rgba(0, 255, 51, 0.2);
		z-index: 11;
	}

	.line {
		height: calc(100% - 2px);
		width: 100%;
		background: linear-gradient(180deg, rgba(0, 255, 51, 0) 43%, #00ff33 211%);
		border-bottom: 3px solid #00ff33;
		transform: translateY(-100%);
		animation: radar-beam 2s infinite alternate;
		animation-timing-function: cubic-bezier(0.53, 0, 0.43, 0.99);
		animation-delay: 1.4s;
	}

	.box:after,
	.box:before,
	.angle:after,
	.angle:before {
		content: '';
		display: block;
		position: absolute;
		width: 3vw;
		height: 3vw;
		z-index: 12;
		border: 0.2rem solid transparent;
	}

	.box:after,
	.box:before {
		top: 0;
		border-top-color: #00ff33;
	}

	.angle:after,
	.angle:before {
		bottom: 0;
		border-bottom-color: #00ff33;
	}

	.box:before,
	.angle:before {
		left: 0;
		border-left-color: #00ff33;
	}

	.box:after,
	.angle:after {
		right: 0;
		border-right-color: #00ff33;
	}

	@keyframes radar-beam {
		0% {
			transform: translateY(-100%);
		}

		100% {
			transform: translateY(0);
		}
	}

	.msg {
		text-align: center;
		padding: 20rpx 0;
	}

	.box2 {
		width: 300px;
		height: 200px;
		position: absolute;
		left: 50%;
		top: 50%;
		transform: translate(-50%, -50%);
		z-index: 20;
	}

	.track {
		position: absolute;
		bottom: -100px;
		left: 50%;
		transform: translateX(-50%);
		z-index: 20;
		color: #fff;
		display: flex;
		flex-direction: column;
		align-items: center;
	}

	.mask {
		position: absolute;
		z-index: 10;
		background-color: rgba(0, 0, 0, 0.55);
	}

	.mask1 {
		top: 0;
		left: 0;
		right: 0;
	}

	.mask2 {
		right: 0;
	}

	.mask3 {
		right: 0;
		left: 0;
		bottom: 0;
	}

	.mask4 {
		left: 0;
	}

	.error {
		color: #fff;
		padding: 40rpx;
		font-size: 24rpx;
		background-color: #333333;
		position: fixed;
		top: 50%;
		left: 50%;
		transform: translate(-50%, -50%);
		width: 550rpx;
		border-radius: 20rpx;
	}

	.error .on1 {
		font-size: 30rpx;
	}
</style>
